12 meter forward stringer replacement
#1
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From: NW Michigan
I’m about to replace forward stringer on SB side from bulkhead to bulkhead. Approx 13.5’ x 10.6”. Question is do I cut the whole stringer out and grind back 10” + - and install new with overlapping glass on the hull about every 2” which day is about 4 or 5 layers of glass??? That’s my thought.
in addition the mini cross stringers that will be replaced as well… can I just leave the old ones and install new a couple inches away rather than removing the old. I don’t see why not but just asking.
I can see what initially caused this is when the 4” holes where drilled for the seat bolt access they never glassed the holes and very poor drain holes at the bottom of resulting in trapping water that either came in from the hatches and or pop up cleats.
tks
John





in addition the mini cross stringers that will be replaced as well… can I just leave the old ones and install new a couple inches away rather than removing the old. I don’t see why not but just asking.
I can see what initially caused this is when the 4” holes where drilled for the seat bolt access they never glassed the holes and very poor drain holes at the bottom of resulting in trapping water that either came in from the hatches and or pop up cleats.
tks
John





#2
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From: Mansfield, TX
I know nothing about fiberglass or fixing stringers so take this with a grain of salt, but would think you would want to cut some kind of a notch pattern in the new and old stringer ends to lock them together and keep them from rubbing and working as much. Either a dentil pattern or maybe a rod system similar to building a log cabin. I've seen others use lag bolts and just bolt overlapping wooden stringers onto the old ones without cutting them out as well, but will add weight.
#3
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From: NW Michigan
The main one I will remove completely. No part of lagging old to new. I’ll likely cut out the mini cross ones that go from the stringer to the outside hull for better glass overlapping.
tks
tks
#6
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From: mckinney texas
#7
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From: mckinney texas
best advice i can give as a non professional. tyvek suits, air supply respirator (i bought a chinese one for $250ish online) i also used a harbor freight dust collector that i ducted outside instead of using the bag. several gross of 34 grit flap disks,( guessing i went thru 70-100of them) and a multi tool cutter. before you start cutting anything douse yourself in baby powder or corn starch. arms legs neck. good luck. don't know if it's necessary but i supported the bottom of my hull before i started cutting anything
#8
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I'll second the tyvek and real good dust protection and raise you the moisture/fume mask from u.s. composites so the resin doesn't knock you out down on the cabin and you come to in a hardened pool of vynil-ester with a roller stuck to the side of your face.
Worse yet you'll have to regrind and start all over.
Reach out to glass dave and ask for advice how to tackle this.
Worse yet you'll have to regrind and start all over.
Reach out to glass dave and ask for advice how to tackle this.
#9
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From: NW Michigan
Dave and I played ph tag today however will reach out again tomorrow. Yeah that itchy scratchy feeling never goes away once you’ve been there. Been there done that and have all the preventatives and precautions already in place. Spent two winters doing pretty much grinding and laying glass etc. But seriously Tks though.






